Silver and gold recovery from precious metal ore deposits have historically been accomplished by treating the precious metal ore with a cyanide solution to dissolve and separate the silver and gold values from the ore gangue, with subsequent processing of the silver and gold cyanide leach solution to recover the precious metals. The Merrill-Crowe process involves digesting a crushed and ground precious metal ore with a cyanide solution to dissolve the silver and gold present in the ore. The cyanide solution containing the dissolved precious metal values is then contacted with zinc dust to precipitate the silver and gold as finely divided metallic particles. The silver and gold metallic particles are recovered by a filter press in the form of a sludge. The sludge, often termed Merrill-Crowe precipitate, in addition to the silver and gold, contains impurities, such as zinc, copper, and iron, and thus is processed by fire refining to produce a dore metal product containing both the silver and gold. The dore metal must be further refined in a number of process steps to separate the precious metals into high purity silver and gold. This known process for recovery of precious metals from the Merrill-Crowe sludge has the disadvantage of involving a number of complex steps and the limitation of processing both silver and gold together into a product which requires refining for separating into high purity silver and gold. A further disadvantage are the environmental problems associated with pyrometallurgy.